Effect of surface conditioning on adhesion of glass ionomer cement to Er,Cr:YSGG laser-irradiated human dentin.

OBJECTIVE

This study aimed to show the effect of dentin conditioner on the bond strength of glass ionomer cement to Er,Cr:YSGG-laser-irradiated dentin compared to conventional bur-prepared dentin.

BACKGROUND DATA

Glass ionomer cement bonds to tooth structure via direct chemical bonding without using any adhesive system. To improve the adhesion of this material, pretreating the dentin surface with a conditioner is recommended. Recently, lasers for tooth drilling have been used for cavity preparation, especially the Er,Cr:YSGG laser. However, there is a lack of research on the bond strength of glass ionomer cement to conditioned Er,Cr:YSGG-laser-irradiated dentin.

METHODS

Extracted human teeth were divided into eight experimental groups and prepared by using either Er,Cr:YSGG laser or a conventional bur. In half of these two groups, the relevant conditioner was applied on the dentin before building up with glass-ionomer cement. After 24 h, all teeth were sectioned, and the microtensile bond strength was determined. The mode of failure was observed, and the fractured surfaces were examined by scanning electron microscopy (SEM).

RESULTS

The use of conditioner was found to significantly affect bond strength for laser-prepared samples (analysis of variance [ANOVA], p < 0.05). Failure analysis showed no adhesive failures in the laser-prepared teeth, and this suggests an effective bond between glass ionomer cement and Er,Cr:YSGG laser-cut dentin.

CONCLUSION

To obtain the maximum retention of a glass ionomer restoration to Er,Cr:YSGG laser-irradiated dentin, the results of this study confirm that pretreatment of the laser-prepared dentin with dentin conditioner is advantageous.